The light would be best described as AN UNCONDITIONED STIMULUS.
An unconditioned stimulus refers to any stimulus which naturally evokes a response from the affected person. The response that is evoked is termed unconditioned response. In the question given above, the light is the unconditioned stimulus while the blinking is the unconditioned response.<span />
The answer is B.
Water in the form of vapor enter the atmosphere. The vapor accumulates in the atmosphere to form clouds. Once the clouds are heavy enough, the water in the form of droplets fall towards land or as rain. It could also be in the form of other precipitation such as snow or hail. As the sun hits the waters in the land, it causes the water to evaporate and the cycle continues.
Answer:
The city was taken off the Detroit water system to save money.
I agree because an ecosystem and a host are basically the same thing.